This invention relates to stethoscopes, and more particularly to a stethoscope consisting of a pair of ear tubes and a chest piece which can receive sounds at two different locations adjacent to each other of a human body.
In medical auscultation, when sound produced in a human body, such as respiratory, cardiac, pleural, or other sound, is caught from two locations adjacent to each other of the body, there is difference between the sound vibrations. It is important to know simultaneously the difference between the two in exact medical diagnosis.
Conventionally, a stethoscope consists of a chest piece or bell having a single sound receiving chamber therein and a pair of auscultatory tubes, i.e., right and left ear tubes connected to the bell. In auscultation by means of the conventional stethoscope mentioned above, the both ears of the observer only can catch the same sound vibration from the chest piece at the same time.
When the usual stethoscope with a single sound receiving chamber therein is used, therefore, it is impossible to hear and recognize the difference between the sound vibrations at two locations adjacent to each other of the human body simultaneously.
A stethoscope of the type having a plurality of microphones in a single body, such as a dual microphone which is the conventional structure having, for example, a bell-shaped microphone diametrically opposed to a diaphragm-type microphone in a single body is already well known in the art. Even by means of the dual microphone type stethoscope, however, the observer cannot recognize the difference between the sound vibrations at two different locations of the human body at the same time.
It has previously been proposed to hear sound at two different locations of a patient body separately by a stethoscope. The above proposed stethoscope consists of a pair of chest pieces and a pair of ear tubes connected with the respective chest pieces. Consequently, in medical auscultation by means of the proposed stethoscope, both ears of the observer can catch the sound vibrations from two different locations of the body at the same time, separately. The pair of chest pieces, however, must be held in the respective hands of the observer. This is too much trouble and inconvenient to examine a patient body.